private static UpgradeStringResult transformXml(
String xml, String newFormatVersion, UpgradeOp... ops) {
try {
DocumentBuilderFactory builderFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder;
builder = builderFactory.newDocumentBuilder();
Document document = builder.parse(new InputSource(new StringReader(xml)));
// Check that this is a NodeBox document and set the new formatVersion.
Element root = document.getDocumentElement();
checkArgument(root.getTagName().equals("ndbx"), "This is not a valid NodeBox document.");
root.setAttribute("formatVersion", newFormatVersion);
// Loop through all upgrade operations.
ArrayList<String> warnings = new ArrayList<String>();
for (UpgradeOp op : ops) {
op.start(root);
transformXmlRecursive(document.getDocumentElement(), op);
op.end(root);
warnings.addAll(op.getWarnings());
}
TransformerFactory transformerFactory = TransformerFactory.newInstance();
Transformer transformer = transformerFactory.newTransformer();
DOMSource source = new DOMSource(document);
StringWriter sw = new StringWriter();
StreamResult result = new StreamResult(sw);
transformer.transform(source, result);
return new UpgradeStringResult(sw.toString(), warnings);
} catch (Exception e) {
throw new RuntimeException("Error while upgrading to " + newFormatVersion + ".", e);
}
}
private static void transformXmlRecursive(Element e, UpgradeOp op) {
op.apply(e);
for (Element child : childElements(e)) {
transformXmlRecursive(child, op);
}
}